• Willy Tarreau's avatar
    fix d_walk()/non-delayed __d_free() race · 7cac57a6
    Willy Tarreau authored
    I checked Jari's explanation below and found that v3.14.77 and v3.12.62
    are missing the same fix as 3.10. In fact Al's original commit 3d56c25e
    ("fix d_walk()/non-delayed __d_free() race") used to mention to check 
    this __d_materialise_dentry() function in the Cc: stable line, but this
    got lost during the backports.
    
    Normally all of our 3 kernels need to apply the following patch that
    Ben correctly put in 3.16 and 3.2. I'm fixing the backport in 3.10.103
    right now.
    
    On Mon, Aug 22, 2016 at 04:56:57PM +0300, Jari Ruusu wrote:
    > This patch for 3.10 branch appears to be missing one important
    > 
    > +       dentry->d_flags |= DCACHE_RCUACCESS;
    > 
    > in fs/dcache.c __d_materialise_dentry() function. When Ben Hutchings
    > backported Al Viro's original fix to stable branches that he maintains,
    > he added that one additional line to both 3.2 and 3.16 branches. Please
    > consider including that additional one line fix for 3.10 stable branch
    > also.
    > 
    > 
    > Ben Hutchings said this on his 3.2.82-rc1 patch:
    > [bwh: Backported to 3.2:
    >  - Adjust context
    >  - Also set the flag in __d_materialise_dentry())]
    > 
    > http://marc.info/?l=linux-kernel&m=147117565612275&w=2
    > 
    > 
    > Ben Hutchings said this on his 3.16.37-rc1 patch:
    > [bwh: Backported to 3.16:
    >  - Adjust context
    >  - Also set the flag in __d_materialise_dentry())]
    > 
    > http://marc.info/?l=linux-kernel&m=147117433412006&w=2
    > 
    > 
    > Also mentioned by Sasha Levin on 3.18 and 4.1 commits:
    > Cc: stable@vger.kernel.org # v3.2+ (and watch out for __d_materialise_dentry())
    > 
    > http://marc.info/?l=linux-stable-commits&m=146648034410827&w=2
    > http://marc.info/?l=linux-stable-commits&m=146647471009771&w=2Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    7cac57a6
dcache.c 86.6 KB